NB SPUTTER COATING ON QWR IN ANU

Abstract

ABSTRACT Nb sputtered QWRs are to be used for the future extension of the Linac. The magnetron sputtering system and its operational performance are described. A magnetron discharge in argon is used for sputtering niobium and in helium for cleaning of the resonator. The cathode comprises two cylindrical and one ring element. The I-V characteristics of the sputtering in argon are given. The superconducting film is deposited with a uniform film thickness and coverage of the resonator. The distribution of the deposition rate f r o m different cathode-resonator geometry and film thickness profiles are discussed. The switching of the cylindrical sputtering cathode from external to internal regions of the cathode, is described. A sputtering procedure, t e s t depositions on ceramic samples and sputtering on the QWR for Time-Energy Lens, will be outlined. The composition of impurities stemming from t h e sputtering process, will be discussed. . I n t r o d u c t i o n The ANU accelerator system, comprising the 14UD and Linac, continues t o evolve toward a competent integrated research facility. The Linac successfully passed important milestones in 1996, including the f i r s t nuclear physics experiment performed on 5 June, and its o f f i c i a l inauguration on 11 July. Good progress has been made in the conditioning of the Pb plated, split loop resonators. Combinations of pulsed RF power conditioning and helium conditioning have enabled all resonators to operate near and above 2 MV/m

    Similar works